人工湿地废水处理机理

对人工湿地的构造、作用机理进行了较详尽的说明,湿地中物理、化学及生物协同作用以及湿地植物输氧造成的湿地基质中好氧、缺氧和厌氧状态的交替出现是保证其对氮磷及有机物具有较强处理效率的原因。研究表明：对进水浓度较低的城市污水,湿地的ＢＯＤ５和ＣＯＤ去除率大于８０％,出水ＢＯＤ２为１０ｍｇ／Ｌ左右。总氮及总磷去除率可大６０％和９０％,较常规二级处理方式具有一定的优越性。     

The Ecotoxicological Recovery of Ely Creek and Tributaries (Lee County, Va) After Remediation of Acid Mine Drainage

The Ely Creek watershed (Lee County, VA) was determined in 1995 to be the most negatively affected by acid mine drainage (AMD) within the Virginia coalfield. This determination led the US Army Corps of Engineers to design and build passive wetland remediation systems at two major AMD seeps affecting Ely Creek. This study was undertaken to determine if ecological recovery had occurred in Ely Creek. The results indicate that remediation had a positive effect on all monitoring sites downstream of the remediated AMD seeps. At the site most impacted by AMD, mean pH was 2.93 prior to remediation and improved to 7.14 in 2004. Benthic macroinvertebrate surveys revealed that one AMD influenced site had increased taxa richness from zero taxa in 1997 to 24 in 2004. While in situ testing of Asian clams resulted in zero survival at five of seven AMD influenced sites prior to remediation, some clams survived at all sites after. Clam survival was found to be significantly less than upstream references at only two sites, both downstream of un-mitigated AMD seeps in 2004. An ecotoxicological rating (ETR) system that combined ten biotic and abiotic parameters was developed as an indicator of the ecological status for each study site. A comparison of ETRs from before and after remediation demonstrated that all sites downstream of the remediation had experienced some level of recovery. Although the remediation has improved the ecological health of Ely Creek, un-mitigated AMD discharges are still negatively impacting the watershed.     

Modelling Wetland Bird Response to Water Level Changes in the Lake Ontario – St. Lawrence River Hydrosystem

Lake Ontario and St. Lawrence River (LOSL) wetland bird abundance and diversity are greatly influenced by lake and river hydrology. Our study used an interdisciplinary ecosystem approach, blending avian and plant ecology, ecohydraulic, statistical ecology and modelling to evaluate potential impacts of water level fluctuations on indicator species representative of the wetland breeding bird assemblages in the entire LOSL freshwater system. Multi-year (2000–2003) bird surveys captured bird distribution and density in wetland habitats under varying degrees of water inandation, depth and fluctuation. Analyses revealed strong associations between estimated breeding pair densities and plant communities, water depth, and degree of water level fluctuation during the breeding season for a suite of wetland bird species using marsh, wet meadow, shrub swamp and treed swamp habitats. These quantitative associations were used to develop wetland bird performance indicators for use in a LOSL water regulation review study. Several bird species also nest at or near the water surface and are thus vulnerable to nest flooding or stranding. Changes to the seasonal hydrology of Lake Ontario and St. Lawrence River that result in an increased frequency or magnitude of these nest failure events may have a significant impact on regional population sustainability. Long term nest record databases were analyzed to create nesting flooding and stranding probability equations based on water level increases and decreases during the breeding season. These species-specific nesting relationships were incorporated into a reproduction index.Many breeding bird species were strongly associated with specific wetland plant communities. Predicted habitat suitability, as measured by estimated breeding pair density, can also change significantly within a specific wetland plant community based solely on changes in water depth during the breeding season. Three indicator species, Black Tern, Least Bittern and Virginia Rail were selected as key environmental performance indicators for alternate regulation plan comparisons.Water regulation criteria should be such that the long term diversity and abundance of wetland plant communities and frequency of spring flooding in marsh habitats during breeding are not reduced. Magnitude and frequency of water level change during the nesting season (May–July) can also adversely impact reproductive success of many wetland bird species. As such, regulation criteria that increase the seasonal magnitude and frequency of water level change may be detrimental to the long term viability of certain regional breeding bird populations.     

Modeling Wetland Plant Community Response to Assess Water-Level Regulation Scenarios in the Lake Ontario – St. Lawrence River Basin

The International Joint Commission has recently completed a five-year study (2000–2005) to review the operation of structures controlling the flows and levels of the Lake Ontario – St. Lawrence River system. In addition to addressing the multitude of stakeholder interests, the regulation plan review also considers environmental sustainability and integrity of wetlands and various ecosystem components. The present paper outlines the general approach, scientific methodology and applied management considerations of studies quantifying the relationships between hydrology and wetland plant assemblages (% occurrence, surface area) in Lake Ontario and the Upper and Lower St. Lawrence River. Although similar study designs were used across the study region, different methodologies were required that were specifically adapted to suit the important regional differences between the lake and river systems, range in water-level variations, and confounding factors (geomorphic types, exposure, sediment characteristics, downstream gradient of water quality, origin of water masses in the Lower River). Performance indicators (metrics), such as total area of wetland in meadow marsh vegetation type, that link wetland response to water levels will be used to assess the effects of different regulation plans under current and future (climate change) water-supply scenarios.The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.     

碎石床湿地去除城镇污水厂出水中磷的研究

为解决城镇污水二级生物处理厂脱磷不达标的问题,设计了潜流碎石床湿地,通过其填料的吸附、沉淀和植物摄取作用,对二级生化处理后的城镇污水进行脱磷试验。结果表明碎石床湿地有较高的脱磷效果,当进水TP为1.74mg/L时,出水为0.25mg/L,去除率为85.63%,同时对BOD5、COD、SS、NH3-N等也有一定去除作用。出水不仅能满足《污水综合排放标准》(GB8978-96)一级,而且满足《城市污水再生利用景观环境用水水质标准》(GB/T18921-2002),污水可以回用。潜流碎石床湿地深度脱磷技术运行费用低、管理方便、环境景观好、有推广应用价值。     

山地小微湿地生态修复探讨 ——以梁平区猎神村梯塘小微湿地为例

小微湿地是乡村景观的组成部分,是乡村重要的水土基础设施.湿地的功能已经得到广泛认同,但过去多关注大面积成片分布的沼泽、湖泊、滨海湿地及大型河流湿地等,而对于那些数量众多、分散分布的小型和微型湿地却缺少关注.2018年10月,《湿地公约》第十三届缔约方大会通过了中国政府提交的《小微湿地保护与管理决议草案》,小微湿地的保护...     

多工艺组合人工湿地在西北农村地区的发展现状及展望

介绍了人工湿地的分类和特点,发展组合人工湿地的原因及国内外近年来多工艺组合人工湿地发展现状及未来趋势,结合实际分析各个工艺的优点与不足.对多工艺组合人工湿地在我国西北农村地区的使用进行分析和展望,可运用组合人工湿地工艺弥补传统水处理工艺的不足,如光催化高级氧化法与人工湿地组合工艺可有效减少水处理时产生的二次污染和土地占...     

Hydrologic and Water Quality Functions of a Disturbed Wetland in an Agricultural Setting1

Abstract: In 2006, we collected flow, sediment, and phosphorus (P) data at stream locations upstream and downstream of a small degraded wetland in south‐central Wisconsin traversed by a stream draining a predominantly agricultural watershed. The amount of sediment that left the wetland in the two largest storms, which accounted for 96% of the exported sediment during the observation period, was twice the amount that entered the wetland, even though only 50% of the wetland had been inundated. This apparently anomalous result is due to erosion of sediment that had accumulated in the low‐gradient channel and to the role of drainage ditches, which trapped sediment during the wetland‐filling phase. In the case of total P, the inflow to the wetland approximately equaled the outflow, although the wetland sequestered 30% of the incoming dissolved reactive P. The discrepancy is almost certainly due to net export of sediment. Many wetlands in the glaciated midwestern United States are ditched and traversed by low‐gradient channels draining predominantly agricultural areas, so the processes observed in this wetland are likely to be common in that region. Knowledge of this behavior presents opportunities to improve water quality in this and similar regions.     

沿黄河下游湖泊湿地植物群落演替及其多样性研究

沿黄河下游湖泊湿地是黄河健康生命系统的重要组成部分,其植物群落演替及其多样性研究对湿地及其生物多样性保护有重要意义。通过野外样地调查,分析了沿黄河下游湖泊湿地植物物种组成及其群落的演替模式,并计算了群落植物多样性特征指数,包括物种丰富度指数（S）、多样性Simpson指数（D）、Shannon-wiener指数（H′）、均匀度指数Pielou（E）。结果表明,研究区湖泊湿地共有77种植物,属于28科61属,除榆树Ulmus pumila Linn.为木本植物外,其余76种为草本植物,其中有1种轮藻门植物,1种蕨类植物;从空间来看植物群落演替过程为沉水植物菹草群落→纯水烛群落→水烛群落→水烛＋扁秆藨草群落→藨草群落→芦苇群落,青龙湖湿地水环境的变化,使湿地植物群落的类型也随之发生变化;群落多样性指数Shannon-wiener指数均低于1.12,Simpson指数为0.41~1,Pielou均匀度指数为0.8左右;芦苇群落的物种数最多,有32个物种,水烛群落以12种次之,菹草群落、水烛＋扁秆藨草群落和扁秆藨草群落中的物种数差别不大。沿黄河下游湿地植物群落多样性水平较低,湿地系统有向陆地系统过渡的趋势。     

植物根系分泌物分析及对湿地微生物群落的影响研究

植物是人工湿地的重要组成部分,其通过根系分泌物对湿地中的微生物群落结构产生影响。本研究分析了美人蕉（Canna indica）、茭白（Zizania caduciflora）、千屈菜（Lythrum salicaria Linn）等3种湿地植物的根系分泌能力及分泌物组成。3种植物的根系分泌物主要组成物质相似,均含有小分子有机酸、酚类、芳香族蛋白质,但各组成比例有所差异。分泌能力则随生长周期持续下降,千屈菜的分泌能力远强于美人蕉和茭白。本研究利用醌指纹研究人工湿地中微生物群落结构,结果发现不同湿地植物对湿地中微生物的组成和多样性产生显著影响。